The problem is called... «Stark»
Williwaw3 июня 2011The problem is called salinization and it means that too much salt is concentrated in the top-soil, attacking the vegetation that grows there. It occurs when the water-table rises, bringing more and more salt to the surface. The water then evaporates, leaving the minerals behind and the land becomes useless. Why is it that the water-table rises? The answer is simple; because all the trees have been cut down. The trees, with their deep roots, used to absorb the water before it could rise, leaving the salt far down below and allowing the water to continue its cycle harmlessly through their leaves hanging high above the ground. Now the trees are gone and Western Australia - like many hot parts of the world where surface evaporation is speedy and the forests have been cleared - faces a terrible problem with the salt of the earth. This is the avalanche factor. Who would have thought that cutting down trees to create agricultural land, would render that land terminally poisoned by salt within a few short years? These days, of course, the cause and effect are wellestablished, but the trees keep falling.
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